To improve spectral efficiency and a user throughput of a communications system, a carrier aggregation (CA) technology, which is also referred to as a cell aggregation technology, is introduced into a Long Term Evolution Advanced (LTE-A) system. The CA technology allows UE to simultaneously perform uplink and downlink communication by using multiple cells, so as to implement high-speed data transmission.
In the prior art, CA inside a base station is included, that is, for one UE, serving cells aggregated by the UE all belong to a same base station, and the base station delivers an activation command or a deactivation command to the UE, so as to activate or deactivate serving cells that belong to the base station. However, for CA between base stations, serving cells aggregated by one UE may belong to different base stations, and one base station in the different base stations generally serves as a master base station of the UE, and another base station serves as a secondary base station of the UE. How to manage activation or deactivation of serving cells that belong to multiple base stations during carrier aggregation is a problem expected to be resolved in the industry.